School-based preventive health education is considered a critical step in the goal to improve children and adolescents' health and to develop lifelong healthy habits. One health enhancing behavior - the development of consistent sleep habits - has received little attention from public health and school officials, despite the knowledge that sleep plays a critical role in effective daytime functioning. Over the past two decades, laboratory data has demonstrated that adolescents across the middle and high school years have an increased need for sleep and experience a phase delay during puberty. Survey and field studies, however, indicate that adolescents obtain less sleep than do younger children. School schedules, extracurricular hours, and other environmental constraints are not beneficial to young adolescents sleep schedules and requirements. In fact, teenagers develop a sleep dept by getting a minimal amount of sleep on school nights and making up for this by sleeping extra on the weekends. As a result of this sleep dept, adolescents may be frequently absent or late for school, sleepy and moody during school hours, inattentive during class time, unable to do their best academically, and prone to accidents and injuries. Remarkably, despite the general agreement among health professionals that health habits need to be taught early in life, few schools include sleep hygiene as part of their health education curricula. The aim of this proposal is to examine the effectiveness of a school-based preventive, sleep education program for improving the quantity and quality of young adolescents' sleep/wake schedules. The three specific aims of the study are as follows: (1) To examine the effectiveness of a sleep education program to teach young adolescents healthy sleep habits; (2) To examine the impact of improved sleep patterns on academic performance and attendance; and (3) To examine potential mediators (e.g., behavior, health) on these relationships.